---
title: 'unstable_buildProxyFunction'
section: 'API'
subSection: 'Hacks'
description: ''
---

# unstable_buildProxyFunction

This function exposes the internal proxy function builder. It's an experimental feauture and you need to understand the [source code](https://github.com/pmndrs/valtio/blob/main/src/vanilla.ts) thoroughly to use it.
